Shotgun shells are NOT made out of Poly Vinyl Chloride (PVC) REPEAT - - NOT!!!
All shotgun shells are made of what is called LDPE or Low Density PolyEthylene.

Your good shells, like the STS or AA or Federal Gold Medals contain lubricating agents within the raw plastic to make the hull more slick and smooth.

The good shells are injection molded, or compression formed. As far as I know the only two shells made this way today are STS and Gold Medals. The AA is a directionally extruded hull with the base wad pressed into place after the hull is manufactured.

Lower priced shells, like Estates, Top Guns, Rio, Diana, and others, are all directionally extruded hulls, or a continuous hollow tube, cut to the exact length, with the base wad (paper or plastic type) inserted after manufacture.

The plastic used in the lower priced hulls is "basically" the same as the better shells, but is lacking the more expensive lubricating additives.

If you burn a modern plastic hull with a cigarette lighter or a small torch, and extinguish the flame, you will notice that the plastic will smell similar to candle wax. . .The plastic will actually "drip" when burned. . .That is the LDPE material!

If shells were made of PVC they would shatter upon firing, and would have little or no resistance to the high heat created at firing. If you've never smelled burning PVC it is really bad. . .Chlorine gas is formed when PVC is burned, and some of you think Top Guns smell bad, you ain't smelled nothing until you've smelled PVC on fire.

I hope you have enjoyed todays chemistry lesson by a guy who's worked in the plastics field for 36 years.

Very interesting posting, but I have a follow up question about some hulls I have. They are "never fired" but never loaded WANDA shells. Appear to be made of a very hard and brittle plastic. The material is red, but transparent, so you could see the components inside. There is no metal base or seperate base wad. Instead of a crimp, a small black plastic cap is provided to hold the shot in place. I've never loaded or fired any of these. What type of material might these be made of? Steve Johnson IL

All the plastic tubes used on our cases are made of high density polyethylene which, once it is extruded, goes through a thermomechanical and bi-directional process which helps to provide excellent elasticity and high mechanical resistance that guarantee our cartridges quality. The cases are containers of the different cartridge components.

The first "see through" shells I can remember were loaded by Alcan. These were also sold as a separate component. The first Wanda shells I used all broke ahead of the rim - probably due to excess headspace in my old M12 before I put in a new headspace ring. I didn't buy any more Wanda shells after that.

Dr. Jones, the only time I've run into "sweating" with plastic shells is on cold days. The water produced by the combustion of the powder condenses in the barrel, including the chamber. The wax from the old paper shells kept those chambers from rusting as did the wax on the old fiber wads for further down the barrels. Since I've not experienced or heard about rusting in the barrels ahead of the chamber with plastic shells, it is probably due to a protective coating of polyethylene from the one piece wads.

I had worked as a safety coordinator for Brown & Root in Houston in the early 70's. One of my areas of responsibility was a safety job at Rhom & Haas working the in the PVC (Chlorine area particularly) and, man talk about precautions! Potent and deadly stuff.

I believe the LDPE is the same material used on bottoms of skis. We used to buy PE sticks to melt to fix gouges in need of repairs and, yes, it does remind me of a candle wax.